1. Field of the Invention
The invention relates to the field of fluid pumps and, in particular, to a type referred to as axial piston pumps.
2. Description of the Prior Art
All known axial piston pumps operate on a principle that a piston reciprocating in a bore will draw in fluid at a first pressure on its return stroke and expel it under a second, higher, pressure on its forward stroke. The return stroke in the above-mentioned prior art piston pumps require additional structures for operation, such as a connecting rod and crank. These additional structures, of course, unduly complicate the piston pump, make it expensive to manufacture, and are a factor to be considered with respect to their reliability. Modern day fluid pumps are also complicated by their use of motors, gears and solenoids which are subject to breakdown.
Another shortcoming of the known prior art pump devices is that, because of the return stroke, the piston's operation is relatively slow. In view of the unique nature of the present invention wherein no return stroke exists, it will be characterized by rapidity of operation.
Finally, there is a dearth in the prior art of axial fluid pumps that generate a low pressure differential at a low flow rate and which are also of low cost. It is believed that fluid pumps of the above characteristics are not readily available in the marketplace because present day technology, which utilizes cranks, rods, gears and motors, is not able to build a pump with the above specifications, i.e., low cost, low flow rate and low pressure differential.